I. Field of the Invention
The present invention is generally directed to carts and specifically directed to a cart with an auger having adjustable elevation.
II. Description of the Related Art
Carts, such as grain carts, shorten harvesting time by improving the efficiency of harvesting equipment such as combines. Carts may be used to transport grain from harvesters or combines in the field to grain trucks or bins at the side of the field. Carts are needed because grain bins are immobile, and grain trucks often do not perform well in muddy or rough field conditions and have the potential to spark fires in dry fields. Carts usually comprise a bin (i.e., hopper or box) sitting atop a wheeled frame in combination with an auger means or mechanism for unloading grain from the bin. Carts handle soft or rough fields with ease and are typically drawn by a tractor alongside a combine, which unloads its contents into the cart. Carts enable a combine to continue to harvest while unloading the grain into the cart. This grain unloading method increases productivity dramatically because combines need never stop to unload. In addition, it is not necessary for the combines themselves to travel to grain trucks or bins at the side of the field each time the combine is full. After a cart is loaded with grain or other material by one or more combines, the grain is unloaded from the cart into a bin for temporary storage or into a waiting grain truck for transport to another location, such as a grain elevator. Because carts offer a combination of economy, versatility, production savings, and maneuverability, carts have been widely accepted by farmers and widely produced by equipment manufacturers.
Carts capable of unloading grain directly into a grain truck or bin use a conveyor to do so. Often the conveyor is an auger. Various auger configurations are known. Auger structures can be contained inside the hopper structure or be located entirely outside of it. Auger configurations can have a single auger or multiple augers. The auger structure can be located at the front, side, back or corner of the cart.
In auger configurations having an auger that extends through the hopper such that there is an auger structure contained inside the hopper structure, grain removal from the hopper can be significantly impaired because internal auger structures hinder downward grain flow, leak grain into the sump causing a high start-up torque, and lessen the depth of the hopper sump area. Therefore, it is desirable that the auger structure is located entirely outside of the hopper.
A double auger configuration has a lower auger and an upper auger. The lower auger receives material from the hopper and deposits it into the upper hopper. The upper auger then carries the material received from the lower auger and deposits it into a trailer, such as a grain trailer. Even triple auger configurations are known having, for example, a lower, horizontally disposed drag auger, a vertically disposed lift auger, and an upper, horizontally disposed discharge auger. However, these plural auger configurations suffer from the disadvantage of increased complexity and cost resulting from the increased number of moving parts and required maintenance. In addition, the likelihood that the material will damaged is increased with each auger.
Carts having a single auger configuration are also known. Compared to multiple auger configurations, single auger configurations are desirable because they are less complex and cause less damage to the grain or other material. One type of single auger configuration is a corner auger. A corner auger extends outwards and upwards from the lowermost portion of the hopper along the corner of the hopper. A folding, corner auger has a retractable section that can be pivoted to a compact, folded position during non-use or travel and to an extended, unfolded position during use. If the retractable section is located at the front of the hopper in its compact, folded position, an operator of the cart can easily view whether the retractable section of the auger is in its compact, folded position or in its extended, unfolded position.
In many prior art carts, the height at which material was discharged could not be adjusted to accommodate trailers, trucks and bins of different heights. As a result, these carts could either be incompatible with tall containers or designed to accommodate the highest container. But, when such a grain cart is used with a shorter container, a gap between the dispensing end of the auger and the container is created. Because material, such as grain, is often light and susceptible to being blown away in windy conditions, the gap increases the amount of material which spills from the auger while attempting to unload the material into the container. Therefore, it is desirable for the elevation at which a cart discharges material to adjustable.
Carts with adjustable discharge elevation are known. Some carts relied on belt conveyors instead augers to discharge material at an adjustable elevation. However, augers are preferred to other types of conveyors, including belt conveyors, because of their simplicity, low cost, durability and versatility. Further, while other types of conveyors are unable to convey material at steep angles, auger operation can continue at any angle.
Carts having adjustable elevation augers are also known. Conventional adjustable elevation augers are often implemented using double augers by using a stationary or fixed lower auger in combination with a moveable upper auger. The stationary lower auger can easily be sealed to prevent material leakage from the hopper, but the range of auger is limited due to the lower portion of the auger assembly being stationary.
Thus, there remains a need for a cart having an auger, and preferably a corner auger, with adjustable elevation that can efficiently unload material without leakage.